Establishment of a leukemia cell line with i(12p) from a patient with a mediastinal germ cell tumor and acute lymphoblastic leukemia.

We report the establishment of a leukemia cell line (UoC-B10) from a patient who developed leukemia several months after the diagnosis of a mediastinal yolk sac tumor. The patient's yolk sac tumor responded to combination chemotherapy, and a mature teratoma with focal areas of hematopoiesis was subsequently resected. However, 5 months after the initial diagnosis, the patient developed an acute lymphoblastic leukemia with a precursor B-cell phenotype. Cytogenetic analysis showed an i(12p) abnormality in the patient's leukemia cells and in the UoC-B10 cell line. The i(12p) was also identified retrospectively in the mediastinal tumor cells by fluorescent in situ hybridization analysis. The UoC-B10 cell line, which has been growing continuously for > 24 months in culture, was Epstein-Barr virus negative and was generally concordant with the patient's leukemia cells by analysis of immunophenotype, karyotype, and genotype. The UoC-B10 cell line possesses receptors for granulocyte-colony-stimulating factor, a cytokine which the patient received as part of his treatment protocol. This cell line may be useful in studying the relationship between i(12p) and hematological differentiation of human mediastinal germ cell tumors.